Notice: Undefined index $_POST [duplicate] - php

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"Notice: Undefined variable", "Notice: Undefined index", "Warning: Undefined array key", and "Notice: Undefined offset" using PHP
(29 answers)
Reference - What does this error mean in PHP?
(38 answers)
Closed 9 years ago.
I am new to php and I made a contact form but i get a
Notice: Undefined index: name in
C:\xampp\htdocs\portfolio\portfolio\html\contact.php
for the lines $_POST - Name, email, message and human.
How can I get take the error away??
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From:';
$to = '86376#ict-idcollege.nl';
$subject = 'Hello';
$human = $_POST['human'];
$body = "From: $name\n E-Mail: $email\n Message:\n $message";
if (isset($_POST['submit'])) {
if ($name != '' && $email != '') {
if ($human == '4') {
if (mail ($to, $subject, $body, $from)) {
echo '<p>Your message has been sent!</p>';
} else {
echo '<p>Something went wrong, go back and try again!</p>';
}
} else if ($_POST['submit'] && $human != '4') {
echo '<p>You answered the anti-spam question incorrectly!</p>';
}
} else {
echo '<p>You need to fill in all required fields!!</p>';
}
}
?>
<form method="post" action="contact.php">
<label>Name</label>
<input name="name" placeholder="Type Here">
<label>Email</label>
<input name="email" type="email" placeholder="Type Here">
<label>Message</label>
<textarea name="message" placeholder="Type Here"></textarea>
<label>*Wat is 2+2? (Anti-spam)</label>
<input name="human" placeholder="Type Here">
<input id="submit" name="submit" type="submit" value="Submit">
</form>

Answer 1

By using isset or !empty:
<?php
$name = (isset($_POST['name']) ? $_POST['name'] : '');
$email = (isset($_POST['email']) ? $_POST['email'] : '');
$message = (isset($_POST['message']) ? $_POST['message'] : '');
?>

Answer 2

Just Make Changes this in your code :
if (isset ($_POST['name'])) {
$name = $_POST['name'];
}
if (isset ($_POST['email'])) {
$email = $_POST['email'];
}
if (isset ($_POST['message'])) {
$message = $_POST['message'];
}
$from = 'From:';
$to = '86376#ict-idcollege.nl';
$subject = 'Hello';
if (isset ($_POST['human'])) {
$human = $_POST['human'];
}

Answer 3

place the code you have above inside a test block as follows
if (isset($_POST['submit'])) {
$name = $_POST['name'];
$email = $_POST['email'];
...
until the end of ?>
this is because when ever the page loads without the form submission. (because you have the control logic and display logic in the same file) it executes the code on the top.